I present Du the ultimate proof that Jack actually caused the incident.

First thing's first:Let's Review The grandfather Paradox for those who don't know it.

"Say Du invent a time muchine Du go back in time and accidently kill your grandfather before he meets your grandmother then Du would have not been conceived therefore Du don't invent the time muchine and Du don't kill your grandpa so Du are conceived which Allows Du to invent a time muchine and kill your grandfather again so Du will be stuck in an endless time loop"